Articles | Volume 22, issue 17
https://doi.org/10.5194/bg-22-4387-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-22-4387-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
04 Sep 2025
Research article |
| 04 Sep 2025
| 04 Sep 2025
A national-scale redox clustering for quantifying CO2 emissions from groundwater denitrification
Department of Geochemistry, Geological Survey of Denmark and Greenland, Øster Voldgade 10, 1350 Copenhagen, Denmark
Julian Koch
Department of Hydrology, Geological Survey of Denmark and Greenland, Øster Voldgade 10, 1350 Copenhagen, Denmark
Birgitte Hansen
Department of Geochemistry, Geological Survey of Denmark and Greenland, Øster Voldgade 10, 1350 Copenhagen, Denmark
Rasmus Jakobsen
Department of Geochemistry, Geological Survey of Denmark and Greenland, Øster Voldgade 10, 1350 Copenhagen, Denmark
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Short summary
Nitrate pollution from farming is a global problem. A natural process called denitrification helps remove nitrate but also releases CO2, which contributes to climate change. Our study shows that CO2 from this process in Danish groundwater may be a major overlooked source – similar to other known agricultural CO2 emissions. This highlights the need to update greenhouse gas reporting to better reflect farming’s full climate impact.
Nitrate pollution from farming is a global problem. A natural process called denitrification...
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